Hey there. You can update to that CPU but I would recommend that you go for a newer AM3 quad core by AMD instead. That way if you ever decide to upgrade your motherboard you can buy an AM3 one and the new CPU will work with it.
I recommend that you wait for a while until ASUS has created a BIOS update for that motherboard that allows the newer phenoms as the current one is in BETA testing which I do not recommend.
Keep an eye on this website
http://www.asus.com/product.aspx?P_ID=0jMy2X8lKstYRvev
That is the ASUS page for that motherboard. Have a look at the CPU support list and keep an eye out for newer releases that support the newer AM3 phenom II's
Jack-O-Bytes